With Steve Jobs reporting for part-time duty a few days a week, many wonder if he in fact got his CEO status back.

Steve Jobs got back to his Apple post a day before his self-imposed deadline, the company told Reuters, CNN, Bloomberg, and other high-profile news outlets. Jobs took a six month medical leave mid-January, installing op-chief Timothy Cook to manage the company during his absence. Steve Downling, chief spokesperson at the California, Cupertino-based gadget giant, confirmed Jobs will initially be working part-time.

Apple shares were virtually flat on Nasdaq following the news, closing at $141.97, down 47 cents, in afternoon trading Monday.

The Silicon Valley welcomes Jobs

An entire Silicon Valley is welcoming Jobs’ return to Apple’s helm. It shouldn’t surprise you: The iPhone maker enjoys iconic status that transcends the Valley. The self-proclaimed consumer electronics giant wields huge power over the computer, cellphone and music industries. Apple is big in Hollywood as well, both symbolically and in terms of real power. Because of this, many greeted Jobs’ return with a sigh of relief. Positive news from Apple certainly bodes well for the Valley and tech industries beyond just computers.

The analyst argued last year that Apple’s shares would lose one quarter of their value, instantly erasing $20 billion of market cap, were Jobs to leave Apple for any reason.

“It would be a disaster,” Munster said at the time. Nowadays, investors no longer fear Apple would tumble without Jobs on board because the company outperformed under Cook’s leadership over the past six months.

As a result of this, the stock is much less volatile to the so-called Jobs factor. Munster, who does not own Apple stock and recommends buying it, says most analysts have updated their estimates accordingly, reducing the negative impact of Jobs-less Apple.

Shares of Apple have surged 66 percent under the six-month Cook watch. Munster summed up Jobs’ current impact on the company’s valuation nicely in a CNN quote saying he’s the “world’s greatest salesman.”

Anatomy of a disease and a PR disaster

Jobs first spooked investors mid-2004 when he informed Apple employees via an email that he had been diagnosed with a rare, less aggressive type of the pancreatic cancer called an islet cell neuroendocrine tumor. Timothy Cook, 48, Apple’s chief of worldwide sales and operations, ran the company for a month while Jobs recuperated from the surgery.

Jobs’ gaunt appearance at the company’s annual developers conference last summer renewed health concerns. Despite Apple’s insistence that the CEO suffered from a “common bug,” investors were frightened by his visibly thin physique. True shock came early January, when Apple put out an open letter, written by Steve Jobs and addressed to “Apple community,” announcing he would not be delivering his trademark keynote presentation at the annual Macworld conference.

The letter cited a hormonal imbalance that has been robbing Jobs’ body off proteins, adding that “sophisticated blood tests have confirmed this diagnosis.” Barely two weeks later, Apple released another carefully worded media advisory, saying Jobs’ health-related issues were “more complex than originally thought.”

Jobs' Mercedes was spotted in Apple's Cupertino campus last week. This week, Jobs is back at work.

On June 20, WSJ asserted that Jobs had received a liver transplant in a Memphis, Tennessee, hospital. Three days later, the Methodist University Hospital officially confirmed the finding, citing Jobs’ personal seal of approval. The doctor who treated Jobs said he was recovering well, dubbing his prognosis “excellent.”

Last week, Jobs was seen on Apple’s campus in Cupertino, California. No new pictures of Jobs have appeared in the media since he hosted the MacBook event last fall. Although Apple has its CEO back, some investors are still unhappy with the fact that the company is treating Steve Jobs’ health as a secret product. Critics warn Apple hasn’t been honest about its CEO’s health, calling SEC to punish Apple for failing to disclose info affecting business metrics.

Is Jobs still the CEO of Apple?

While Jobs return to Apple’s helm is certainly an encouraging sign, Downling’s carefully worded statement leaves a lot to be desired, raising more questions than answers. How many days is exactly a “few days a week”? Apple’s hype machine gave no information about the liver transplant or Jobs’ current health status. An Apple spokesman even declined to tell whether Jobs was at the office during Monday.

The fact that Apple didn’t bother to put out a press release to formally explain its CEO’s return leaves room for speculation. Is Apple hiding something about Jobs’ CEO status? Is interim CEO Timothy Cook still in charge of day-to-day CEO operations, like he has been during Jobs’ absence? Is Jobs now a CEO or an adviser to Apple’s board, as some analysts have been suggesting?

We simply don’t know any of this because Apple isn’t talking. Until the company unambiguously clears these issues, there’s a high degree of certainty that Timothy Cook will soon be promoted into the next CEO of Apple. If that’s where Apple is heading, then Jobs may step down completely or assume a new role of providing the vision and strategic input.

Jobs’ life-saving liver transplant is certainly a tough enough operation for far healthier and younger individuals, let alone a cancer survivor at the age of 54. Factoring in his fragile health, it’s entirely possible that Jobs leaves daily business hoopla to someone else, preserving his strength for strategic thinking.

Looking at the bigger picture, Jobs has most likely been prepping his farewell over the course of past two years. Conspiracy theorists buy this idea, believing that the Macworld announcement, the open letter, and the liver transplant “leak” are but carefully staged PR stunts designed to gradually prep Steve Jobs’ exit with a minimum impact on the Apple stock.

What about you? Do you think Jobs is still Apple’s CEO now that he reported back for work? Or is now the time for him to step down? Will Apple survive without Jobs? Do share your thoughts with us by posting in the comments below.